Strong results in mining exports have led to significant growth in the Australian economy, according to the Bureau of Statistics (ABS).

Australia's economy is growing at an annual rate of 3.1 percent, up from 2.4 percent three months ago, the ABS reported late on Wednesday.

The strong start to 2018 marks a significant increase in the rate of growth in seasonally adjusted terms.

Bureau figures indicate quickening growth in the March quarter was driven mostly by exports of mining commodities, in particular coal, iron ore and liquefied natural gas.

Export growth accounts for half the increase in gross domestic product, government spending for about a third.

Some economists are not surprised by the increased growth, which they say aligns output growth with jobs growth, which was unsustainably high at 3.5 percent in 2017.

Andrew Hanlan, an economist with one of Australia's big four banks, Westpac, said on Thursday: "This is against the backdrop of stronger global growth, which accelerated in 2017 to the fastest pace since 2011."

In the past four quarters, Australia's economy has grown by 1.01 percent (March), 0.54 percent (December 2017), 0.52 percent (September 2017), and 1.03 percent (June), bringing the annual growth rate to 3.1 percent.

Economists, however, say the strong rise in net exports over the past three months is unlikely to be repeated.

Data shows exports of goods were up 2.9 percent, powered by non-rural exports, with mining commodities, liquified natural gas, coal, iron ore and non-monetary gold the main drivers, which helped net exports rebound from their poor showing in the December quarter.

Paul Dales, chief economist at Capital Economics, told the Australian media: "We doubt that the strength of net exports will be sustained as some of it was due to a catch-up after production problems in the middle of last year."

The ABS is the independent agency of the Australian government, providing key statistics on a range of economic, population, environmental and social issues.